package com.hmdp.utils;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {
    private final StringRedisTemplate stringRedisTemplate;
    /**
     * 开始时间戳
     */
    private static final long BEGIN_TIMESTAMP = 1735689600L;
    /**
     * 序列号位数
     */
    private static final long COUNT_BITS = 32;

    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    //keyPrefix用于区分，比如订单号，用户id，商品id等等
    public long nextId(String keyPrefix) {
        //1.生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond - BEGIN_TIMESTAMP;
        //2.生成序列号
        //2.1获取当前日期,精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        //2.2自增长
        Long increment = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
        //3.拼接返回
        return timestamp << COUNT_BITS | increment;
    }
    public static void main(String[] args) {
        LocalDateTime time = LocalDateTime.of(2025, 1, 1, 0, 0);
        long second = time.toEpochSecond(ZoneOffset.UTC);
        System.out.println(second);

    }
}
